A 63-year-old woman operated eight months ago for glioblastoma (GB) located in posterior fossa was admitted to emergency room for stuporous, nausea, vo-miting and headache. CT and MR showed recurrence of posterior fossa cystic-necrotic tumour without any other intracranial contrast enhancing lesion. Tumour was removed near totally. Perseverative cerebrospinal fluid (CSF) fistula from the incision was occurred and contaminated by multidrug resistant Acinetobacter ba-umannii. Two months after the tumour removal she was expired because of the septicaemia. GB located in posterior fossa is uncommon in both adults and child-ren; and it appears as two different subsets: de novo (primary type) and secondary glioblastomas. Although our patient's immunohistochemical findings werenot enough to demonstrate the tumour subset, we have thought that her tumour was de novo because of no other brain involvement, staining with GFAP, vimentin, and nearly absent p53 mutation.